Multiple gas burner



Feb. 12', 1957 W. P. AYERS MULTIPLE GAS BURNER Filed Nov. 20, 1952 m MW M/YLLJAW 2? 19223123 United States Patent MULTIPLE GAS BURNER William P. Ayers, Lombard, Ill.

Application November 20, 1952, Serial No. 321,643

2 Claims. (Cl. 158-104) This invention relates to a gas. burner of the type used with furnaces, boilers, and the like, as described in the specification of the co-pending application Serial No. 207,752, filed January 25, 1951, of which this application is a continuation in part.

According to the invention, the burner proper includes a mixing tube for supplying combustion fuel to a series of refractory radiant burners. The tube presents a row of openings around each of which is a simple and positive locking arrangement for securing the radiant burners thereto. The tube is so shaped as to provide for the automatic mixin of air and fuel introduced therein and for a substantially uniform flow of combustible fuel mixture to each radiant burner.

in the accompanying drawing, Figure l is a top plan view. with a portion broken away, of a mixing tube embodying principles of the present invention; Figure 2 is a side view in elevation of the mixing tube on which is illustrated the connection or looking arrangement there with of refractory radiant burners; Figure 3 is an end view in elevation of the mixing tube as seen when viewed from the right hand end of Figure l; Figure 4 is a fragmentary side view in elevation of a modified form of the locking arrangements by which the refractory radiant burners are connected to the mixing tube; Figure 5 is a view diagrammatically illustrating the mixing of air and fuel in the mixing tube; and, Figure 6 is a view, similar to Figure 2, of a modified form of mixing tube construction.

As explained in the specification of the said co-pending application, the mixing tube 12 supplies fuel to a series of radiant burners 13, 13 and is preferably of rectangular or square section and tapers upwardly, as defined by the bottom wall 20, from an intermediate portion toward the forward end. At the most reduced end of the tapered section the mixing tube is crimped and upturned as at 23 to effect a closure. Although a sloping wall, such as wall 20, is desirable it is not necessary as the gas burner will operate efliciently with a mixing tube having a uniform cross-section along its length.

in Figures 1 and 2 there i illustrated the connection of the hollow burners to the mixing tube. The top surface of the tube is perforated or punched outwardly to provide a plurality of spaced fuel feed openings 24, 24. Material, usually metal, displaced by the punching operation efiects a flared edge 25 around each opening. A refractory radiant burner, having a hollow base 26, is positioned over each fuel opening boss and anchored to the mixing tube by sealing the space around the flared edge 25 and 'the adjacent inner surfaces of the burner base with a ceramic cement 27.

A detailed description of the radiant burners is not given herein as the construction thereof forms an independent part of this invention.

In Figure 4, is illustrated a modified embodiment of the anchoring construction on the mixing tube for the burners. In this embodiment, the fuel openings are punched outwardly to form nipples 29, 29 the outer surice faces of which are roughened or knurled, as at 30, to form numerous grooves and undercut edges for holding the ceramic cement.

At the end of the mixing tube, opposite its'tapered end, there is provided fuel supply inlets. Spacedinwardly from the closed end of the tube is an opening 31 in the bottom wall through which primary air is drawn; It is preferred that this opening be adjustable as-to size-to regulate the flow of indrawn air. This was provided; as set forth in the originally filed application, byanadjustable registered opening in the burner housing.

An axial opening 33, in the end wall of the mixing tube, receives therein an endwis'e adjustable fuel jet ornozzle orifice 34. The jet threads .into a T-connection SS whereby it may be axially adjusted so that the tapered end 36 is positioned in the opening 33.

In Figure 5 is diagrammatically illustrated the automatic mixing of the gas fuel and primary air in the mixing tube 12. By adjusting the inlet of air flow through opening 31 the desired volume of air is admitted to mix with gas fuel to provide a combustible mixture to the radiant burners.

The stream of gas fuel emerging under pressure from the jet or nozzle tip 34 is directed axially lengthwise of the mixing tube in an area generally defined at 59 in Figure 5. As it progresses along the tube it expands radially and mixes with the air entering through the primary air inlet. During travel of the air and gas fuel lengthwise of the mixing tube, the square corners in the tube automatically effect a turbulence as shown thereby resulting in a thorough mixing of the fluids before reachin g the burners.

Friction between the fluids and the sidewalls of the tube effects a progressively slower velocity of mixture flow as the combustible mixture travels along the tube. In order that the volume of fluid flow be uniform to all of the burners, the mixing tub is tapered at its forward end as previously described. This progressive reduction in cross-sectional area of the tube insures a more nearly uniform volume of ga fuel and air mixture to each burner, Without regard to the position thereof along the length of the tube, by increasing the velocity toward the end of the tube.

The effect of increasing the velocity of a combustible mixture is also accomplished in a tub of modified construction shown in Figure 6. The tapered construction of the tube, on which the burners are mounted, is the same in the tubes shown in Figures 2 and 6. At the 0pposite end of the modified form of mixture tube, the construction provides a venturi arrangement. The tube section 66 i round in cross-section and circumferentially tapered from its ends toward the center thereof. At the free end thereof, the tube terminates in a cylindrical portion 67. Although not shown, the fluid inlets 31 and 33 are similarly provided to operate in the same manner as described with the mixing tube of Figures 1 and 2.

By the foregoing construction, the gas fuel and air entering the mixing tube at the end 67 flows at greater speeds through the reduced neck 63 and also through the tapered en-d defined by the wall 26. This double change in velocity efiects a more active turbulence with resultant better mixture of fluid and also more nearly constant volumes of combustible mixture to the burners.

While i have thus described and illustrated specific embodiments of my invention, I am aware that numerous alterations and changes may be made therein without departing from the spirit of the invention or the scope of the appended claims.

I claim as my invention:

1. In a heating device, a metal manifold through which a mixture of air and gas passes, said manifold having a wall formed with openings punched out of the metal, outwardly flared spaced apart portions of metal extending from the edges of each of the openings, said flared portions of metal at each opening defining a nipple, burner members of refractory material having hollow bases, said hollow bases being fitted over the nipples and ceramic cement sealing the space between the flared portions and the adjacent inner surfaces of the burner bases so that the burner members are securely bonded onto the nipples concentric to the openings.

, 2. In a heating device, an elongated manifold through which a mixture of air and gas axially passes, said manifold having a flat top wall formed with a plurality of longitudinally spaced openings punched out of the wall, outwardly flared spaced apart portions of metal up tanding from the edges of the openings and defining nipples, burner members of refractory material having hollow bases, said hollow bases being fitted over the nipples, and ceramic cement sealing the spaces between the portions of each nipple and the adjacent inner surfaces of the hollow base of the associated burner member so that the burner members are securely bonded onto the nipples concentric to the openings, said manifold having inlet openings for receiving air and gas.

References Cited in the file of this patent UNITED STATES PATENTS 365,899 Bielefeld July 5, 1887 1,241,032 chnieder Sept. 25, 1917 1,830,393 Genrink et a1 Nov. 3, 1931 2,255,636 Wittmann Sept. 9, 1941 2,403,139 Thiele July 2, 1946 2,585,835 Preiss Feb. 12, 1952 2,701,610 Carlson Feb. 8, 1955 FOREIGN PATENTS 487,445 Great Britain June 21, 1938 

